The market place as well as the patent literature are not without representative systems for the handling of toxic fluids such as liquid pesticides widely used, for example, in the field of agriculture in the form of a spray to combat insects, plant diseases and the like.
Exemplary of disclosures in the patent literature are U.S. Pat. Nos. 3,913,606, 3,916,924, 3,976,087 and 3,993,221.
There remains, however, considerable room for improvement, particularly in view of recent more stringent governmental regulations requiring a closed system of handling liquids possessing a high level of toxicity, such as category one pesticides which display the signal word DANGER on the label and are considered the most toxic and hazardous, and category two pesticides which are considered moderately toxic and display the signal word WARNING on the label.